Stoichiometry-dependent mechanical properties of pyrogallol–isonicotinamide cocrystals†

Abstract

Mechanical properties of multicomponent compounds are largely dependent upon the intermolecular interactions between the components and obviously on the overall crystal packing. Herein, we have shown the modulation of mechanical properties of two cocrystals between pyrogallol (PG) and isonicotinamide (INMI) by altering the stoichiometry of the components. One of the cocrystals shows elasticity and the other shows brittleness. Analysis of the crystal structures of the cocrystals revealed the difference in the intermolecular interactions and crystal packing, leading to different mechanical properties.